Imperfect immunity: estimation and epidemiological implications

The persisting burden of vaccine-preventable infections underscores challenges associated with the imperfect immune response elicited by many vaccines. I introduce statistical problems undermining causal inference of imperfect vaccine efficacy and effectiveness, motivating the use of models to account for the natural history of infectious agents. I next describe ongoing work applying such models toward questions around the re-emergence of mumps in vaccinated populations, the strength of immune protection against diarrheal pathogens, and the vanishing burden of otitis media (middle ear infection) among children.